Heterologous expression of cellular adhesion molecules

Abstract

Methods for the production of unicellular photosynthetic organisms capable of producing cell adhesion proteins are disclosed. DNA constructs as well as methods for integration of the DNA constructs into the genomes of unicellular photosynthetic organisms for the expression of cell adhesion proteins are also disclosed.

We claim: 
     
       1. A transgenic unicellular photosynthetic organism chosen from  Chlamydomonas  spp, and  Dunaliella  spp., having a DNA construct stably integrated into the unicellular photosynthetic organism's genome under conditions suitable for expression of said DNA construct in an extracellular matrix, cell wall, plasma membrane or outer membrane of said unicellular photosynthetic organism, wherein said DNA construct comprises a promoter, wherein said promoter is operably linked to a cell adhesion protein coding sequence, wherein said cell adhesion protein coding sequence is chosen from an Algal-CAM protein, an ISG protein, a V1 protein, a V2 protein, a cadherin protein and a claudin protein wherein said cell adhesion protein coding sequence is expressed as a heterologous protein in the extracellular matrix, cell wall, plasma membrane or outer membrane of the organism, and wherein the expressed cell adhesion protein induces the unicellular photosynthetic organism to flocculate by adhering to one or more unicellular photosynthetic organisms. 
     
     
       2. The transgenic unicellular photosynthetic organism of  claim 1 , wherein said cell adhesion protein coding sequence of said DNA construct is chosen from SEQ ID NO:1, SEQ ID NO:3, SEQ ID NO:5, and SEQ ID NO:7. 
     
     
       3. The transgenic unicellular photosynthetic organism of  claim 2 , wherein said cell adhesion protein coding sequence of said DNA construct further comprises said cell adhesion protein coding sequence operably linked to a downstream regulatory region coding sequence. 
     
     
       4. The transgenic unicellular photosynthetic organism of  claim 3 , wherein said cell adhesion protein coding sequence of said DNA construct further comprises a translation regulator coding sequence operably linked to said promoter. 
     
     
       5. The transgenic unicellular photosynthetic organism of  claim 1 , wherein said cell adhesion protein coding sequence of said DNA construct further comprises a selectable marker coding sequence operably linked to said promoter coding sequence. 
     
     
       6. The transgenic unicellular photosynthetic organism of  claim 5 , wherein said selectable marker coding sequence of said DNA construct further comprises a reporter protein coding sequence operably linked to said cell adhesion protein coding sequence. 
     
     
       7. The transgenic unicellular photosynthetic organism of  claim 1 , further comprising a transit peptide sequence specific to the transgenic unicellular photosynthetic organism, wherein said transit peptide sequence is operably linked to said cell adhesion protein coding sequence, wherein said transit peptide sequence causes expression of the cell adhesion protein coding sequence in the extracellular matrix, cell wall, plasma membrane or outer membrane of the organism, and wherein the expressed cell adhesion protein induces the unicellular photosynthetic organism to flocculate by adhering to one or more unicellular photosynthetic organisms. 
     
     
       8. The transgenic unicellular photosynthetic organism of  claim 1 , wherein said cell adhesion protein coding sequence is an amino acid sequence chosen from SEQ ID NO:2, SEQ ID NO:4, SEQ ID NO:6, and SEQ ID NO:8.